In many businesses related to the forestry and nursery industries, the measurement and recording of certain tree characteristic information, such as tree diameter, location, quality or grade, type of tree and the like, are determined and recorded for the purpose of making an inventory. For the forestry industry, inventorying large stands of trees can help determine or approximate the future value of the lumber that will be harvested when the trees are cut down. Likewise, in the nursery industry, inventorying nursery tree stock is also important for determining the value of the trees that will be sold during the upcoming sales season. Inventorying a nurseries' stock of trees is also important so that the nursery knows how many trees of a particular variety, grade and size it can sell during the sales season.
In the past, inventorying trees has largely been performed manually using a caliper-like device to measure tree diameter and writing down the information in a paper inventory log. Typically, for the nursery industry, inventory information for each tree includes the location of the tree, the type or variety of the tree, the grade or quality of the tree, as well as the diameter of the tree. Unfortunately, manual recording of this information is slow and labor intensive, especially when it is considered that the manually recorded information is usually later manually transcribed or rerecorded into a computer.
In an attempt to address at least some of these challenges as they are presented in the lumber industry, Luikko, U.S. Pat. No. 5,022,162, discloses an electronic caliper having a display and means for inputting alphanumeric information into a record that can be stored in a computer memory. To determine the diameter of a log, a moveable jaw is slid by an operator of the caliper toward a fixed jaw of the caliper until the two jaws bear against the log. When performing this measurement, the distance between the two jaws is shown in the display. Thereafter, a switch is pressed to enter the measurement shown in the display of the caliper into memory. To selectively input other numbers, and even letters, when prompted, the movable jaw of the caliper is moved along an arm of the caliper by the operator until the jaw indicates the desired number or letter and thereafter the switch is pressed to enter the selection into memory.
Unfortunately, this method of data entry is rather slow and tedious, requiring the operator to spend a considerable amount of time to manually slide the jaw along the arm to take a measurement before entering it into memory. Additionally, the operator must spend valuable time to directly manipulate the moveable jaw to select a desired number or letter before entering it into memory. Moreover, a person using such a caliper must undesirably bend down or kneel, if measuring the diameter of the trunk of a standing tree close to the base or bottom of the tree being measured, further wasting time and quite possibly causing discomfort to the operator if a large number of trees are being measured. Although the apparatus disclosed in the Luikko patent may be better suited for inventorying cut logs that have been horizontally stacked, its poor ergonomics make it poorly suited for inventorying vertically standing trees and, more particularly, for inventorying large groups of standing trees. Finally, as a result of these drawbacks, the apparatus disclosed in the Luikko patent is simply impractical for use in quickly inventorying large stands of trees having, for example, two hundred or more trees.